Update dependencies from...

Update dependencies from https://dev.azure.com/dnceng/internal/_git/dotnet-wpf-int build 20200118.2 (#2451)

- Microsoft.DotNet.Wpf.DncEng - 5.0.0-alpha.1.20068.2

eng/Version.Details.xml

@@ -75,9 +75,9 @@
       <Uri>https://github.com/dotnet/corefx</Uri>
       <Sha>a434a52ae3f1175bc1cad8b1a02b0921ef3b1f55</Sha>
     </Dependency>
-    <Dependency Name="Microsoft.DotNet.Wpf.DncEng" Version="5.0.0-alpha.1.20066.12">
+    <Dependency Name="Microsoft.DotNet.Wpf.DncEng" Version="5.0.0-alpha.1.20068.2">
       <Uri>https://dev.azure.com/dnceng/internal/_git/dotnet-wpf-int</Uri>
-      <Sha>5e28cb5faea5134f8bedb4d21bfebc565c822403</Sha>
+      <Sha>9550c3349ffee769128ab1ded5798f18fc3a15d8</Sha>
     </Dependency>
     <Dependency Name="System.IO.Packaging" Version="5.0.0-alpha1.19504.7" CoherentParentDependency="Microsoft.NETCore.App">
       <Uri>https://github.com/dotnet/corefx</Uri>

eng/Versions.props

@@ -114,6 +114,6 @@
       It is worth reiterating that this package *should not* be consumed to build the product.
   -->
   <PropertyGroup>
-    <MicrosoftDotNetWpfDncEngVersion>5.0.0-alpha.1.20066.12</MicrosoftDotNetWpfDncEngVersion>
+    <MicrosoftDotNetWpfDncEngVersion>5.0.0-alpha.1.20068.2</MicrosoftDotNetWpfDncEngVersion>
   </PropertyGroup>
 </Project>